Protractor-level



E. L. POWELL AND H. J. ALBERSWORTH.

PROTRACTOR LEVEL.

APPLICATION FILED APR.17,1919.

Patented May 11, 1920.

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EL'WOOD L. POWELL, 0F PHILADELPHIA, PENNSYLVANIA, AND HENRY J. ALBERS- WORTH, OF ST. LOUIS, MISSOURI.

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i Specification of Letters Patent.

Patented May 11, 1920.

Application filed April 17, 1919. Serial No. 290,659.

To all whom it may concern:

Be it known that we, ELWooD L. POWELL, a citizen of the United States, residing at Philadelphia, in the State of Pennsylvania, and HENRY J. ALBERsWoRTH, a citizen of the United States, residing at St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Protractor-Levels, of which the following is a specification containing a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

Our invention relates to an improved inclinometer, which we have denominated a protractor level, and it consists in the novel construction and combination of parts hereinafter particularly described and claimed.

- The object of our invention is to provide an improved .level, which will be devoid of the usual liquid bubble container that is liable to be accidentally broken during use, and to produce an accurate level that may be used as an inclinometer for all of the purposes for which levels and inclinometers are used, and which shall be simple and reliable in construction and operation, as well as durable, and of low cost.

In the drawings,

Figure l is a top plan view of a level constructed in accordance with our invention.

Fig. 2 is a front side elevation of same.

Fig. 3'is a cross-section, taken on the line 3-3 of Fig. 2.

Fig. 4 is a detail cross-section of the weighted and pivoted indicating-member, taken on the line 4-4 of Fig. 5.

Fig. 5 is a detail front-elevation of the indicating-member, and

Fig. 6 is a diagrammatic view, illustrating the development of the graduations upon the outer periphery of the indicating-memher.

In carrying out our invention, in its present form, we provide a body or frame 1, which is the same in external form as the body or frame of levels heretofore in use, and it may be made of any suitable material, such as wood (in the case of levels for the use of carpenters, brick-layers and other mechanics in the building trades), or it may be made of cast metal, as here shown, and provided with webs 2 lightened by removing the metal to form openings 3 in said webs.

Formed in the said body or frame 1, at

about the center of its length is a chamber 4,

An indicating-member 9 is made in the form of a wheel, preferably cast from aluminum or other metal, and is provided with an axial bore 9. The outer periphery, as well as the front face of said wheel 9, are both provided with graduations or other marks from O to 360 degrees, which. extend completely around said periphery and said face.

Hereinafter we shall refer to the said indicating-member as the indicating-wheel, or merely as the wheel 9.

The graduations upon the face of said wheel 9 are designated by the numeral 10, those upon the periphery of the wheel being designated by the numeral 11..

Formed in the said wheel 9, at a point about diametrically opposite the location of the said O or zero mark, is a weightpocket 12 in which is eccentrically placed such a quantity of lead or other heavy substance 14 as will cause the said wheel to always hang with said weighty-substance atthe bottom of the wheel, and with the said zero marks at the top of said wheel, when said wheel is suspended in said chamber 4 upon the pivoting-means now to be described, no matter to what degree the said wheel'and its frame are relatively rotated axially during the practical use of the instrument in leveling, plumbing, or in measuring the inclination of any object.

The said wheel 9 is mounted to turn freely to an unlimited degree upon its pivotingmeans, in either direction.

The pivoting-means for said. wheel 9, in the present form of our invention, are de scribed as follows:

An axle or pivot-pin16 is fixed, by a driving fit, in the said bore 9' of said wheel, and the bearing in the front end of said pivot-pin is engaged by the inner end of a This chamber is r of the faceplateo, and secure said transparent material, by means of common rivets -19, to the said face-plate.

A zeromark, or fixed mark 8, is placed upon'the inner 'surfaceof the said sheet of mica or other transparent material 18, at the center of the length of said sight-openings, foran obvious purpose.

The operation of our invention need not be further described, as the same will be understood by those accustomed to use levels, plunibs and inclinometers.

- However, it may be explained that in measuring the inclination of the undersides of ceilings,either the top or bottom of the frame 1 may be placed in contact with said parts, and still the reading may be taken, as

the said indicating-wheel and said frame are relatively free to rotate ineither direction, as before described, no matter -'what the angle assumed by the frame.

We claim the following as our invention:

[An improved protractor level and plumb comprising a frame or stock; an indicatingwheel having graduation-marks upon its periphery .and upon its side and eccentrically-weighted; a removable face-plate L- shaped in cross-section and having sightopenings in its two faces; means for securing said face-plate over a :recess that is formedin said frame; apivot-pin fixed ina central bore of the :said indicating-wheel and having bearings in its iOPPOSlf/Q :ends a fixed :pintle carried :by said ifaee-plate :and "projecting into the bearing (in one end of said .pivot pin; and "an adjustable bearing- 'pintledn the form oflascrew thatiis thread ed through the wall of the recess in said frame at a point opposite the isaidrfixed pintle, and the inner end of which adjustable pintle projects into the adj acent bearing in said pivot-pin.

ln testimony whereof we :have signed our names to ithis specification in the presence of two subscribin witnesses.

ELW OD L. POWELL. HENRY J. ALBERSWORZIH.

*Witnesses: i

EDWIN .C. TAYLOR, .JoHN 1O. THIGDON; 

